diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2023-04-01 19:59:46 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2023-04-05 12:33:32 +0100 |
| commit | c20c57d9868d7f9fd1b2904c7801b07e128f6322 (patch) | |
| tree | fab449903c49484160029890fc35061b7f109131 /drivers/spi | |
| parent | 43bac5158bcc5fe392a17457fda1f8e33a13e458 (diff) | |
| download | linux-next-c20c57d9868d7f9fd1b2904c7801b07e128f6322.tar.gz | |
spi: fsl-spi: Fix CPM/QE mode Litte Endian
CPM has the same problem as QE so for CPM also use the fix added
by commit 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian"):
CPM mode uses Little Endian so words > 8 bits are byte swapped.
Workaround this by always enforcing wordsize 8 for 16 and 32 bits
words. Unfortunately this will not work for LSB transfers
where wordsize is > 8 bits so disable these for now.
Also limit the workaround to 16 and 32 bits words because it can
only work for multiples of 8-bits.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
Fixes: 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian")
Link: https://lore.kernel.org/r/1b7d3e84b1128f42c1887dd2fb9cdf390f541bc1.1680371809.git.christophe.leroy@csgroup.eu
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-fsl-spi.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c index 702756c25aa7..4651f65c9046 100644 --- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -181,8 +181,8 @@ static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, struct spi_device *spi, int bits_per_word) { - /* QE uses Little Endian for words > 8 - * so transform all words > 8 into 8 bits + /* CPM/QE uses Little Endian for words > 8 + * so transform 16 and 32 bits words into 8 bits * Unfortnatly that doesn't work for LSB so * reject these for now */ /* Note: 32 bits word, LSB works iff @@ -190,9 +190,11 @@ static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, if (spi->mode & SPI_LSB_FIRST && bits_per_word > 8) return -EINVAL; - if (bits_per_word > 8) + if (bits_per_word <= 8) + return bits_per_word; + if (bits_per_word == 16 || bits_per_word == 32) return 8; /* pretend its 8 bits */ - return bits_per_word; + return -EINVAL; } static int fsl_spi_setup_transfer(struct spi_device *spi, @@ -222,7 +224,7 @@ static int fsl_spi_setup_transfer(struct spi_device *spi, bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi, mpc8xxx_spi, bits_per_word); - else if (mpc8xxx_spi->flags & SPI_QE) + else bits_per_word = mspi_apply_qe_mode_quirks(cs, spi, bits_per_word); |